Monday, January 28, 2013

January 28th, 2013

Fresh Air Matters... with Capt. Yaw

The first major grounding of a commercial aircraft type since 1979 took place last week. The Boeing Dreamliner, a remarkable machine, pushing the barriers in many directions, grounded over a battery issue. There a number of things we need to think about before we jump to conclusions, especially after listening to some of the more dramatic media presentations.

First of all, what was the problem in 1979? It was a problem with the DC10 related to its engines parting company with the wing. The maintenance procedure used, against the advice of McDonnell Douglas, was probably the cause of the fault. It appears that they used a forklift to change an engine, and cracked an engine pylon in so doing. The consequential loss of life, on that flight out of Chicago, changed a lot of things. As we have said before ‘every regulation has a tombstone’. For the DC10, after a lot of inspections, changes in procedures and the like, the fleet was returned to service and continued in production for many years. The type still flies many millions of kilometres every year, especially with FedEx! Personally, I enjoy flying in the DC10 when I get the chance!

The current B787 situation is very different. The world has changed, and our approach to safety is much more brisk and sharp. The people who gave up their lives, in a DC10, in 1979 have given us a legacy in relation to safety and grounding of aircraft types in 2013. We all take safety a lot more seriously these days – and it is a good thing. In this 787 grounding it appears to be principally ‘Battery problems’. No loss of life. No major emergency. Just battery problems – and a bold decision to make headlines, through being open about them, and grounding the fleet worldwide.

The battery appears to have overheated and caught fire. This is not good. The aircraft safety systems reported the fire. This is good. The pilots took appropriate action. This is very good. Everybody is fine. This is excellent. Boeing are taking it seriously. This is what we expect – they are taking their responsibilities in the matter, and want to fix it.

Technically, they could replace the battery and go flying again. But no. They want to know why. What happened? Could it happen again? That is the basis of aviation safety.

Aviators like to know WHY? And they like to prevent it happening again! If only all modes of transport took the same approach!

Apparently, a spokesman for the NTSB is reported as saying “We’re looking at everything that could have played some role in this battery mishap. There’s a lot yet to learn.” This is excellent. An admission that there is a lot more to learn.

What is different about this battery? It uses a different technology, which makes it lighter. Lighter means that the aircraft can carry more cargo… But how many kilos lighter than the previous technology? A rough estimate is nearly half of the weight for the same output. All in all a tiny percentage of the overall aircraft weight – but a significant amount if you add up those kilos and multiply by the life time of kilometres travelled, it then equates to significant amounts of fuel being burned over the lifetime of the aircraft, just to carry a heavier battery array…

Why can’t they just change to another battery type anyway? It is not that simple. Due to the regulations and approvals, a change in the battery will require a lot of paperwork, potential changes to circuits and charging systems – and a lot of drawings, tests, etc. prior to being considered for release to flight. Furthermore, the 787, as part of its design, has higher electrical needs, and then the fact that the type of battery used in the Dreamliner is not necessarily the same shape, size or package as the older technology may mean that the physical space for the battery could be an issue. I am sure that it could be done. But it should not be done unless necessary – and not until we know what happened and why.

What type of battery are they using? The same as found in many smart phones – Lithium Ion. Light, efficient, but if not managed properly can suffer from ‘Thermal-runaway’ – a condition where once they start to overheat they just keep on overheating - which is what may have happened to the Boeing planes.

It takes a lot to get something approved for flight, so how come this battery was approved and then failed? It could be a quality control challenge at the factory in Japan where these batteries are made (Yuasa). It could be a handling issue (think back to the DC10). It could be a circuit issue. It could be climatic. It could be anything at this stage, hence “We’re looking at everything that could have played some role in this battery mishap. There’s a lot yet to learn.”

The Dreamliner entered service in October 2011. So what has happened since? Why are only some playing up? Should they let the ‘no problem planes’ continue to fly? Should they just change all the batteries and go back into the air? It is not that simple – and you and I are very glad the Boeing people are not going for any ‘easy solution’. They will approach this with the same detail as they did their work related to sending people to the moon and moving around on it! Boeing has been a major player in the space race, and knows what it means to design it, build it, test it and back it up in service – anywhere on the planet – or off of it for that matter!

I have every confidence that within a relatively short time, the 787 will be Dreamliner-ing its way across the skies, and that we will all have learned a great deal. Indeed, in this particular case, I have a particular interest.

Only last week, we considered trying a Lithium Ion battery in one of our aircraft! They are light, and as a result may give us not only more power, but less weight in our next aircraft build. At approximately 50% of the weight for the same power with a lot of other advantages (lifetime, recharge profiles, etc.) it could be a viable solution for some of our local aircraft… one day.

There have been cases of Lithium Ion batteries being a problem in the past with certain computers, and that was fixed. However, this technology is still relatively new in aviation applications. I think we will wait another year or so before we try it – but we will monitor the developments!

Finally, as a matter of interest, the Airbus A380 also uses the same battery technology and, I am sure, will be watching this matter with great interest… perhaps the two elephants of the airliner world will share notes on this one – and both grow stronger!

One thing is certain, and that is when we fly, we know that Safety in the skies is no accident… a lot of people work hard to ensure that this industry stands out for the right reasons… even if some of the media sometimes spins it the wrong way!

Capt. Yaw is Chief Flying Instructor and Chief Engineer at WAASPS, and lead Pilot with Medicine on the Move, Humanitarian Aviation Logistics (www.waasps.com www.medicineonthemove.org e-mail capt.yaw@waasps.com)

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